Electric clock mechanism



J1me 1934- c. E. LARRABEE ELECTRIC CLOCK MECHANISM Filed May 18, 1931' a Sheets-Sheet 1 NVENTOR O n M o a 6 4 S V 6 v ,.h E 51? 2 LE: 1:51 7w n 2 5 J1me 1934- 'C. E. LARRABEE ELECTRIC FLOCK MECHANISM Fild May 18, 1951 a Sheets-Sheet 2 INVENTOR BYfllv ATToRNE June 12, 1934.

c. E. LARRABEE ELECTRIC CLOCK MECHANISM Filed May 18, 1931 s Sheets-Sheet s INVENTOR BY ATTORNEY l supply.

Another object of this invention is to pro- Patented June 12, 193 4" I PATENT" OFFICE UNiTED STATES morale cnocx macnsmsu Clinton E. Larrabee, Binghalnton, N. Y., assignol', by mesne assignments, to International Business Machines Corporation, New York, N. Y., a corporation of New York Application May 1:,1931, Serial No. 538,231

10 a time controlled contactor for operating a minute impulse time indicating mechanism from a commercial current supply having devices incorporated therein for connecting said mechanism after an interruption of the commercial current vide a time controlled contactor for emitting periodic electrical impulses at a normal rate of one impulse each minute to operate a minute 2 impulse time indicating mechanism direct from the commercial supply and for emitting said periodic electrical impulses at a more rapid rate after an interruption otthe commercial current during which one or more of the normal periodic impulses were renderedinefl'ective.

A further object of the invention is to provide a time controlled contactor having a single contact for initiating normal periodic electrical impulses and for initiating periodic electrical impulses at a rate faster than normal after an interruption ofthe current supply having a duration of a period longer than that occurring between the normal periodic impulse.

A still further object of the invention is to provide a time controlled contactor 01' a unitary structure adapted to be attached to any one of a number of different kinds of minute impulse mechanisms to control the operation of the unit to which it is attached.

Another object of the invention is to provide a time controlled contactor comprising a spring driven escapement mechanism controlling the opening and closing of a contact, said mechanism being adapted to be mounted in cooperative relav tion to a minute impulse operated time indicating mechanism whereby said time indicating mechanism may be operated directly from a source of a commercial power under the control of said time controlled contactor.

Another object is to provide a time controlled contactor adapted to operate a minute impulse time indicating mechanism from a current supply and to connect said indicating mechanism after a period of idleness due to. an interruption in said current supply.

I Various other objects and advantages of my invention will be obvious from the following particular description of one form of mechanism embodying the inventionor from an inspection of the accompanying drawings; and the inven- 80 tion-also constitutes certain new and novel features of construction and combination of parts hereinafter set forth and claimed:

Fig. 1 shows a front elevation view of the con-- tactor with part of the front mounting plate cut away;

Fig. 2 shows a side view of contactor mounted on a secondary movement;

Fig. 3 is a detailed section of the spring winding mechanism taken on lines 3--3 of Fig. 2;

Fig. 4 is a detailed section taken on lines 4-4 of Fig. 1;

Fig. 5 is a detailed section of the contactor mechanism shown in Fig. 1 with the parts inposition when the contactor closes. Fig. 6 is a detailed section of winding mechanism shown in Fig. 3 with the parts in a different position. v

Fig. 7 is a diagrammatic view of the electromagnet control circuit.

Time indicating. mechanism which are of the minute impulse type are well known and operate through the medium of receiving-an electrical impulse each 'minute to advance the type wheels or other indicating numbers. In-

.terruptions of the current supply from which the still more intricate systems where self regulation is accomplished.

Although the minute impulse type is not necessary for a straight time indicating device such as the ordinary wall clock yet it is much simpler of construction, and therefore much less costly, but

where a time stamp or job recorder, or any type of machine that prints a record is required a minute jump is most desirable so that the type wheels are set in printing position at all times except for the instant that the jump is made from one minute position to the other. By using the old and well known method, it would require a master clock and control equipment to operate a single unit as well as a number of units, so that the expense involved for a person only wanting a single unit would be rather excessive.

The present invention provides a very simple and compact unit which may be mounted on a single minute impulse device whereby this unit may be connected to any ordinary commercial source of current supply and be operated accurately and in addition the present invention provides a simple connecting means for compensating for current interruptions with a reasonable limit.

For the sake of simplicity the contactor is shown mounted in connection with a minute impulse type of secondary clock movement rather than to a more complicated time registering device. It will be understood, however, that this contact-or is adapted to be mounted in conjunction wtih any type of minute impulse mechanism.

The contactor is assembled and mounted between two mounting plates and 11 which are rigidly held in spaced relation to each other by spacers 12 having one end riveted or otherwise rigidly fixed to plate 11 and the other end threaded and protruding through plate 10 and adapted to receive nuts 13. This unit is mounted to the front plate 14 of the secondary movement.

Secondary movement Asthe minute impulse secondary movement used in the present-embodiment is fully described and explained in the allowed application of C. E. Larrabee, Serial #308,227 filed September 25, 1928, and now Patent No. 1,821,100 only a general description sufficient to understand its operation will be given. The secondary movement is mounted on two plates 14 and 15 held rigidly in spaced relation to each other in the usual well known manner. A double pole magnet 16 is mounted between the two plates and a, laminated armature 17 is rotatably mounted between the pole faces 18 of said magnet. This armature 18 is fixed to a shaft 19 (Fig. 2) which is journalled in the supporting plate 15 and an auxiliary supporting plate 15 on which is fastened across the pole pieces 18 of the magnet.

Fixed to one end of the shaft 19 is a disk 20 having fixed thereto a pin 21 eccentric to the center of the disk and on which is pivotally mounted a pawl 22. This pawl is normally held in cooperation with a ratchet wheel 23, said pawl being so freely pivoted about its support that it maintains this cooperation by gravity. A retaining pawl 24 freely pivoted on a pin 25 which restricts to the plate 14 also coacts in the same manner with the ratchet wheel 23. A spring 26 fastened to the screw 27 on the disk 20 biases said disk and therefore the armature 17 in a counter clockwise direction. 'When the magnet is energized the armature is turned in a clockwise direction driving the pawl 22 over the ratchet wheel picking up the next succeeding tooth and when the magnet is deenergized the spring 26 moves the armature 1'? in a counter clockwise direction to advance the ratchet wheel and therefore the hands 28a and 29a of the clock. These hands are mounted in the usual manner on the spindle 28 and the sleeve 29 respectively. The usual reduction train from the minute hand to the hour hand is shown with the gear 30 being fixed to the shaft 31 which in turn is fixed to the ratchet wheel 23 and journalled in the plates 14. and 15, said gear 30 being connected to the train of gears 32, 33 and 34 to the sleeve 29 which carries the hour hand. A portion of the dial 35 is shown in dotted lines to indicate its relation to the hands of the clock. This foregoing description constitutes the minute impulse, secondary unit to which the time controlled contactor which will now be described is attached.

Time control contact The mechanism of the time control contact is mounted between the plates 10 and 11 previously described, the rotating parts being journalled in said plates. The time controlling element may constitute any type of escapement.

For the sake of simplicity and conservation of space we have shown in the preferred embodiment a well known type of escapement comprising a balance wheel an associated hair spring 41. a verge lever 42, a verge 43 and a coacting escape wheel 44. This escapement is driven through the gear train 45, 46, 47 and 48 (Fig. 2) by a spring 49 (Figs. 3 and 4) housed in a spring drum 50 which is rigidly attached to the gear 48. This gear and drum are pivotally mounted on a shaft 51 and the outside of the spring 49 is attached to the drum and the inside or center of the coil is fixed to the shaft 51. Fixed also to this shaft 51 is a ratchet wheel 52 which is adapted to be rotated in a counterclockwise direction by the actuation of the pawl 53 and to be restrained from clockwise motion by the retaining pawl 54 pivoted at 55 to a stud mounted on the plate 11. Pawl 53 is pivotally mounted at 56 to an arm 5'7 of a U-shaped member having its one arm 57 pivoted to the stud 55 f Fig. 3) and its other arm 58 (Fig. 1) pivoted to a pin 59 mounted in the plate 10. These two arms are rigidly connected by the integral cross member 60 and a rigid cross pin 61 rigidly fixed in each arm so that the two arms move in unison.

It will be seen that the oscillation of the arm 5'7 about its pivotal point 55 will cause a counterclockwise rotation of the ratchet wheel 52 through the actuation of the pawl 53 which is held in coaxial relationship with the ratchet by means of the spring 62 and that the turning of this ratchet wheel and therefore the shaft 51 will tend to wind up the spring 49 on said shaft therefore biasing the spring barrel 50 in a counterclockwise direction to drive the escape train. A pin 63 is fixed in the ratchet wheel 52 and a pin 64 is fixed in the gear wheel 48 (Figs. 1 and 3). The spring is inserted in the spring drum with sufficient initial tension so that when two pins 63 and 64 abut as shown in the drawings the spring is at its maximum desired tension.

The arm 58 is biased in a counterclockwise direction by a spring 65 which spring is of slightly greater tension than the maximum allowed tension of the spring 49. Therefore, if the arms 57 and 58 are lifted in a clockwise direction about their pivotal points so that the pawl 53 engages the next succeeding tooth of the ratchet wheel 52 and then if said arms are released the spring 65 being of greater tension than the spring 49 will cause the ratchet wheel 52 to rotate counterclockwise immediately to wind the spring 49 providing the pins 63 and 64 are not abutting each other and prevent any further winding of said spring 49. If they are in contact the pawl 53 will catch in the next succeeding tooth and continue to hold said pins in contact and the arms will drop only as fast as the ratchet wheel will turn which will be dependent on the rate the time escapement operates or in other words.

V 1,902,744 4 thetime'ent at that time will be driven directly from the-spring 65 through the arms 58 and 5'7 through the pawl 53 to the ratchet wheel, through the pins 63 and 64 to the gear 48 and thence through the train previously described to the escapement mechanism. Pivotally mounted on the arm 58 are two pawls 66 and 67 biased in a counterclockwise direction by springs 68 and 69 (see Figs. 1 and 5). These pawls coact with a ratchet wheel '70 made of some suitable insulating material said ratchet wheel being rotatably mounted with respect to and on the shaft '51 (Figs. 1' and 4). As the arm 58 oscillates the ratchet wheel '70 is moved in a counterclockwise direction on both the upstroke and the downstroke of the arm 58. The pawl 66 moves the ratchet on the downstroke and the pawl 6'7 moves it on the upstroke. The relative motion of the pawls being different so that the movement of the ratchet on the downstroke is greater than the movement on the upstroke. This proportionate movement is definitely for the purpose of timing the operation of contact arms '71 and '72 which are controlled by the tooth members of this ratchet wheel which serve as cam points.

As the arm 58 descends the contact arm '71 drops off of its cam point and makes a connection closing the contact with the contact arm 72.

This contact remaining closed when the arm 58 has reached the bottom of its travel which is limited by the tail piece 73 integral with the arm its cam point by virtue of the cam having been rotated on the upstroke, as the pawl 67 is moved to the left engaging the tooth of the cam '70 as viewed in Figs. 1 and 5. This action causes contacts '71 and '72 to break contact thus deenergizing magnet 16 and permitting arms 5'7 and 58 to resume their downward movement again under the influence of the spring 65.

The contact arms '71 and '72 are mounted between suitable insulating blocks to a bracket '75 fixed to plate 10. The connection between the time controlled contactor and the impulse secondary movement is established by means of a member '76 fixed to an extension of the pin 21 and.v to a pin '77 also mounted in a disk 20 so that said member '76 oscillates when the disk 20 oscillates and the pin '74 which is rigidly mounted at one end of the'member '76 abuts the tail piece '73 and carries it upward when the armature 1'7 mechanisms not shown which may not be adapt-- ed to be actuated in the same manner as the minute impulse mechanism shown in this embodiment.

The knurled hand knob '79 is fixed to the end of a micrometer screw which. engages a threaded member on the end of the regulating lever 80. This is for the purpose of regulating the timing of the escapement which is well known and old in the art.

The operation of this mechanism may now be clearly understood. With the parts as shown in Fig. 1 the arm 58 moves downward slowly at a rate determined by the escapement rotating the ratchet wheel '70 as previously described until it reaches a position as shown in Fig. 5 in which the contacts '71 and '72 make contact with each other at which time the magnet 16 is energized and causes the armature 1'7 to be rotated thus advancing the hands of the clock one minute and lifting the arm 57 by means of the pin '74 as described which again moves the ratchet wheel '70 sufficiently to break contact with the contact members '71 and '72 thereby deenergizing the'magnet 16 and allowing the spring 65 which has been retensioned by this operation to again take control and repeat the cycle. The teeth on the ratchet wheel are so spaced that the escapement may be regulated to cause these contacts '71 and '72 to be made once each minute. In event of the interruption of the current the magnet 16 will fail to operate and the arms 5'7 and 58 will remain in the position as shown in Fig. 5. The escapement: however, will continue to operate from the power stored in the spring 49 and as this spring begins to unwind the pins 63 and 64 will separate inasmuch as the pin 63 will be held stationary due to the failure of the ratchet wheel 52 to be operated:

When the interruption of the power supply is terminated and the power is again available the magnet 16 will immediately become energized and cause the arm 5'7 to be picked up and released in the manner previously described but as the pins 63 and 64 are not together the spring 65 will not be held back by the escapement but will immediately drop to wind the spring 49 and as it drops each time will cause the contacts '71 and '72 to make and energize the magnet so that the arm 5'7 will continue to oscillate up and down rapidly until the pin 63 has followed around to 120 again abut the pin 64. In this way, there will be as many oscillations of the arm 5'7 as there were minutes of interruption of the power circuit so that the time indicating mechanism will have been advanced to compensate for the number of minutes it was stopped due topower failure.

While there has been shown and described and pointed out the fundamental novel features of the invention as applied to a singlemodification, it will be understood that various omissions and substitutions. and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention therefore to be limited only as indicated by the scope of the following claims..

I claim: I

1. In an electric clock mechanism an electric magnet and power supply therefor, an armature associated with said magnet, a first power storing means associated with said armature, a second power storing means operable by said first power storing means. a cam operated by said first power storing means, a contactor associated with said cam for controlling said electro magnet, a time indicating means controlled by said elec- .tro magnet, a timing mechanism normally operated by said first power storing means for timing the operation of said contactor, means associated with said magnet, a spring fixed to said armature, a time indicating device operable by said spring, power storing means releasably associated with said armature, a cam 0perated. by said power storing means, a contactor associated with said cam for controlling said electromagnet, and a timing mechanism operated by said power storing means for timing the operation of said contactor.

CLINTON E. LARRABEE. 

